Pressure Sensor Measures Blood Pressure From Inside Arteries
Vacuum panels are particularly good for insulating buildings – as long as the vacuum does not leak. A tiny pressure sensor constantly checks the condition of the vacuum and indicates whether the insulation effect is still present.
Mrs Miller is happy. Since she moved to the new apartment building she has not had any nasty surprises on her heating bills. This is because the building is insulated with a new material which exhibits particularly low thermal conductivity and therefore high energy efficiency. Vacuum insulation panels consist of a tightly sealed shell and porous core material made of silicic acid. This serves to support the vacuum in the insulation panel. Because a vacuum is a very good thermal insulator, the insulation value of the vacuum panels is five to ten times higher than that of conventional panels, for instance those made of polystyrene.
The panels are sensitive, however. Over the years the airtight film loses its insulating effect and the vacuum leaks. Experts put the increase in gas pressure at 1 millibar per year. Another problem is that because the film is very thin it can be damaged during transport. Before being installed the panels therefore have to be checked to see whether the vacuum and insulating effect are still present. So that the condition of the panels can be determined at any time, research scientists at the Fraunhofer Institute for Microelectronic Circuits and Systems IMS in Duisburg have developed a tiny pressure sensor. »The pressure sensor is placed in a recess inside the panel. On the board next to the microchip there is a transponder with a coil which transmits the measured data through the film without any hard wire connection. A reader on the outer wall of the panel receives the measured data and supplies the transponder with energy using a second coil,« explains Dr. Hoc Khiem Trieu, head of department at the IMS. »The sensor consumes very little energy and is extremely small, measuring only around 20 square millimeters. A further special feature of the tiny sensor is that it draws its energy from the reader’s radio signal even through thin metal layers. It is therefore also suitable for measuring the vacuum in refrigerators, where low thermal conductivity is likewise essential.«
The sensor is used in the medical field, for instance to measure blood or eye pressure. It has now been developed further for the construction sector. »The sensor is presently at the prototype stage. The aim is to put it into series production in one to two years’ time,« states Trieu. The IMS will be showcasing the sensor at Euro ID, the trade fair for automatic identification, in Cologne from May 4 to 6 (Stand A12).
AST Updates CE Approval For Its Pressure Sensor
American Sensor Technologies, Inc. (AST) has updated and expanded its CE approval for its pressure sensor, transducer, transmitter and switch product families. AST products with the CE logo conform to EMC Directive 2004/108/EC for Electromagnetic Compatibility.
Tested by the independent laboratory, TUV Rheinland in Newton, CT, each product was evaluated for performance against radiated emissions, electrostatic discharge (ESD), radiated immunity, electrical fast transient (EFT), surge immunity, conducted immunity, and power frequency magnetic field immunity.
Products were tested and approved to the following standards:
| EN61326-1:2006 | EN61326-2-3:2006 | EN61000-6-1:2007 | EN61000-6-3:2007 | EN55011:2007+A2:2007 & FCC Part 15 , ICES-003 | EN55011:2007+A2:2007 & FCC Part 15 (Radiated Emissions) |
| EN61000-4-2:1995 + A1:1999 +A2:2001 | EN61000-4-3:2006 | EN61000-4-4:2004 | EN61000-4-5:2005 | EN6100-4-6:2007 | EN61000-4-8:1993 + A1:2001 |
Products approved to the new standards include:
AST2000, AST20HA, AST4000, AST4200, AST4300, AST43LP, AST4310, AST4400, AST44LP, AST4410, AST4500, AST4510, AST4520, AST4600, AST46HA, AST4700, AST4710, AST47LP, AST47HP, AST47SM, AST4900, Model1000 and Model5000.
Ultra-Thin Absolute Pressure Sensor
San Juan Capistrano, CA – Meggitt Sensing Systems announces the debut of Endevco® model 8515C, a miniature, high-sensitivity piezoresistive pressure transducer, designed for surface air flow and other aerodynamic measurements requiring high output in a small, lightweight package.
The ultra-low profile design of Endevco® model 8515C has an overall thickness of 0.030 inch (0.76mm) and diameter of 0.250 inch (6.3mm). Units are available in ranges of 15 and 50 psia, with 200 mV full scale output, and frequency responses of 180 kHz and 320 kHz, respectively. The transducers offer stable performance over an temperature operating range of -65 to +250°F (-54 to +121°C), with combined non-linearity, non-repeatability and pressure hysteresis error of less than 0.50% FSO. In addition, model 8515C is designed to survive 10,000 g shock and 10,000 g acceleration, with minimum 5X burst pressure, making it the best performing pressure transducer of its kind in the industry.
Model 8515C is supplied with an integral cable, and is typically surface mounted onto curved surfaces, for minimal effect on laminar air or hot gas flow. A flush mounted fit may also be achieved by recessing both transducer and lead wires into the mounting surface, while using a supplied protective screen to prevent particular impingement. For airflow smoothing requirements within flight test applications, an optional rubber fairing is available. Modified versions of model 8515C are also available for wider temperature compensation. All units are shipped in special electrostatic discharge (ESD) packaging, for added protection during product shipment and handling.
Because of its uniquely high overload capability, high frequency response, very low base strain sensitivity and excellent temperature performance, model 8515C is ideally suited for small-scale wind tunnel testing models, helicopter or turbine blade surface pressure measurements, as well as aerodynamic surface measurements required during flight test. For detailed specifications, drawings or additional information about Endevco® model 8515C or other products, visit www.endevco.com.
Meggitt Sensing Systems
www.meggitt.com
Basic Low Voltage Pressure Sensors from All Sensors
Morgan Hill, CA — All Sensors Corporation announces a new line of Basic Low Voltage Pressure Sensors. The new Basic Low Voltage Pressure Sensor product family consists of two product series, the Basic Low Voltage (BLV) Series and the Basic Low Voltage Reference (BLVR) Series. Both the BLV and BLVR are based upon All Sensors’ CoBeam2 TM Technology. CoBeam2 TM Technology helps reduce package stress as well as greatly improves position sensitivity when compared with competitive sensors. The BLV Series device utilizes a single die technology while the BLVR Series utilizes a dual die reference technology to reduce all output offset or common mode errors. The BLV and BLVR Series devices provide a high output signal at a low operating voltage. This is the result of an extremely sensitive sensing element capable of operating at low supply voltages. Lower operating voltages result in improved errors due to warm-up shift. The BLV and BLVR afford design engineers a new basic pressure sensor capable of low pressure measurement with improved energy efficiency. The Basic Low Voltage (BLV) Series is available in 1, 5, 10, 20, and 30 inH2O pressure ranges. The Basic Low Voltage Reference (BLVR) Series is also available 1, 5, 10, 20, and 30 inH2O pressure ranges.
The sensors are offered in a pc board mountable package. Multiple port configurations are available including gage and differential devices.
The BLV and BLVR employ All Sensors’ CoBeam2 TM Technology. Both devices provide a basic, uncompensated mV output. The BLVR Series device employs a dual die reference technology to reduce all output offset or common mode errors. The BLV Series device is specified at 1.8 volt excitation with 1mW power consumption. The BLVR (dual die) is specified at 3.3 volt excitation with 7 mW power consumption. Low operating voltage offers increased energy efficiency.
All Sensors
www.allsensors.com
Pressure Sensor Designed For Pneumatic Applications
Ifm’s compact PQ Series pressure sensors are designed for pneumatic applications typically found in robotics and material handling applications. The sensors precisely measure the full range of pressure and vacuum typical in these applications.
The cube-shaped pneumatic pressure sensor easily retrofits traditional pressure switches at a fraction of the price. Measuring only 32mm x 30mm x 42mm, the compact sensor can be installed in areas with limited mounting space.
Application parameters are established using two pushbuttons. The bright, four-digit display indicates system pressure and can be clearly seen from long distances. The sensor features two programmable switching outputs or one switching and one diagnostic output. In addition, the values can be programmed to change color depending on the switching output status (e.g., red if output 1 is switched; green if output 1 is not switched).
The technology is based on a piezo-resistive measuring element. The silicon measuring cell is insensitive to liquids (e.g. condensed water) and deposits that might occur in the system. The cell changes resistance when pressure is applied. The stress induced in the cell is transformed into an electric signal that is proportional to the pressure. The silicon measuring cell guarantees a high overload resistance as well as an accuracy of ± 0.5%.
For mounting purposes, the PQ pressure sensor can be fixed to flat surfaces and profiles using the sensor’s two M4 drill holes located in the front of the sensor. The PQ can be mounted to a DIN rail or connected to plates or manifolds using ifm’s robust DIN rail bracket. The sensor can be connected to air lines through the G-1/8 port using a 6mm or 8mm tubing adapter or a 1/8″ NPT adapter.
Two models are available. PQ7809 has a measuring range of -14.5 to 14.5 psi and the PQ7834 has a measuring range of -14.5 to 145 psi. Electrical connection is made through an M8 Pico DC connector.
Kavlico’s Common-Rail Pressure Sensor
Moorpark, CA – Kavlico has designed a sensor to measure common-rail pressure in diesel engines. The advantages of monitoring common rail pressure are many; including increasing engine power & torque, improving fuel economy, reducing engine noise, and improving vehicle drive-ability while creating cleaner exhaust emissions. With today’s restrictive emissions standards, keeping exhaust particulate emissions within the mandated levels is a must… and Kavlico’s common-rail sensor is an essential element of the common-rail injection system.
Pressure is regulated and monitored by the Electronic Diesel Control Unit (EDCU) which receives an electronic input from the Kavlico pressure sensor. The sensor operates on 5 Vdc and provides a 0.5 to 4.5 Vdc linear amplified analog output proportional to pressure to the EDCU. The highly accurate and ruggedly designed sensor uses a thin film TiON sense element which provides highly reliable and repeatable measurements.
The cost-effective sensor is EMI/EMC protected, has low power consumption, and is capable of operation in high vibration environments. Fully temperature compensated across the entire measurement range, the sensor has an operational temperature of -40ºC to 125 ºC.
Pressure ranges are available from 0 to 3,000 Bar or 40,000+ PSI. The sensor can be customized to accommodate a wide array of pressure ports and electrical connector options dependent upon each OEM application-specific requirement. Alternative pressure ranges and output formats are also available upon request.
Kavlico
www.kavlico.com
Custom Sensors & Technologies
www.cstsensors.com
Pressure Sensor Provides Full Scale Millivolt Output
Morgan Hill, CA – All Sensors Corporation announces the release of a ½ inH2O Full Scale Millivolt Output Pressure Sensor. This announcement marks the first ½ inH2O Millivolt Output Pressure Sensor released to the market. Obtaining a ½ inch measurement from a millivolt device has become possible utilizing proprietary All Sensors’ CoBeam2™ Technology. The ½ inch device is an addition to the existing family of 1 to 30 inH2O Millivolt Output Pressure Sensors. The ½ inch device offers 2x the sensitivity of the 1 inH2O device which provides higher signal to noise for the most demanding low pressure applications. For the first time customers can now obtain ½ inch pressure measurements from a millivolt output device. This pressure range has traditionally only been available as an amplified device. This millivolt pressure sensor offers accurate, low pressure measurements at a more affordable price point. The entire ½ to 30 inH2O pressure sensor family is RoHS compliant.
Package Features The sensors are offered in a pc board mountable package with two pressure ports. Seven pressure ranges are available from ½ inH2O full scale to 30 inH2O full scale. The dead volume to each pressure port is matched for superior common mode response.
Electrical Features The sensors are available with a millivolt output proportional to either gage or differential pressure. Output offset errors are significantly reduced by electrical cross coupling compensation employed within the sensor. Position sensitivity is virtually immeasurable by utilizing proprietary All Sensors’ CoBeam2™ Technology.
Applications Ideal applications for this device are medical breathing (Lung function, Respiratory monitory, Sleep diagnostics, and Drug delivery systems), HVAC, and process automation.
Price Contact factory for price. Samples are available for product testing.
Low Pressure Transducers from Gems
Plainville CT – Gems® Sensors & Controls™ announces the launch of the new 3300 series pressure transducer. The 3300 series transducer is designed for low pressure applications that demand small size and low cost along with high accuracy and stability. The 3300 Series pressure transducer is well suited to applications such as chemical sterilizers, autoclaves, pneumatics, HVAC&R, pumps & compressors.
The 3300 pressure transducer is the newest addition to the highly successful 3100 and 3200 series transducers, bringing a versatile low pressure capability to the product line and opening up a host of new applications across a number of different industries. All stainless steel wetted parts and all welded construction make the unit compatible with harsh chemicals and environments. In addition, the unique temperature compensation at source technology delivers outstanding temperature stability.
The 3300 series is available in pressure ranges from 15 to 250 psi and is capable of operating over a temperature range of -40°F to 257°F. Available in voltage, current, and ratiometric outputs, with a wide selection of connectors, pressure fittings and mating connectors makes the 3300 suitable for many applications without modification.
Gems Sensors & Controls
www.GemsSensors.com
Accuracy vs. Resolution
Purpose: To describe the difference between “accuracy” and “resolution” for silicon based pressure sensors.
Application: Any application.
Discussion: Silicon based pressure sensor inherently have infinite resolution. The limit to the practical use of this limitless resolution is based upon many factors associated with the compensation and amplification of the output signal and the accuracy demanded by the application.
All the figures show an output signal where the output of the sensor is displayed as a signal quantized (stepped) by an analog to digital converter after some amplification of the pressure sensor signal. For ease of display the steps are relative to each other and not representative of a typical system. For instance a relatively low accuracy system would be an 8-bit system resulting in quantization of the signal into 256 steps (28). As a practical matter for today’s sensors and added electronics the limit to the resolution with accuracy acceptable to most applications is roughly one part in sixty thousand, or a 16-bit system (216). For such a system the analog to digital converter would be somewhere between 18-bits to 24-bits.
All Sensors
www.allsensors.com
Secondary Process Seal Assembly with Rupture Indication Sensor
April 7, 2009 by R. Nelson Parrish
Filed under Pressure
SYRACUSE, N.Y. – Cooper Crouse-Hinds has developed a smart, more user-friendly version of its Secondary Process Seal Assembly. Designed to prevent the passage of pressurized gases through conduit, cables and conductors, the new and improved Secondary Process Seal provides increased protection over the original, plus a new Rupture Indication Sensor that provides an immediate notification of a potentially explosive seal rupture.
The Rupture Indication Sensor saves time and labor costs, as it is able to quickly sense the buildup of pressure inside the fitting. The sensor provides immediate notification of a primary seal rupture, allowing maintenance personnel to quickly address the problem and isolate safety concerns. The sensor opens at 60 psi, and its stainless steel construction provides superior corrosion resistance and reliability.
The enhanced, user-friendly design of the new Secondary Process Seal has a number of convenient features. Most notably, the simplified design reduces the time associated with installation, decreases maintenance costs and reduces facility downtime. Plus, the integrated packaging contains all the necessary components for a seamless installation, without the hassle of pouring seals.
“As a leader in explosionproof technology, Cooper Crouse-Hinds is committed to developing innovative products and solutions to the global marketplace,” said Dave Holloway, General Manager, Productivity Solutions at Cooper Crouse-Hinds. “The Secondary Process Seal works to increase workplace safety while decreasing labor and potential downtime. With its simplified, user-friendly design, it truly is a one-of-a-kind solution.”
The Secondary Process Seal contains an explosionproof drain that allows for the safe release of gas, vapor or liquid from the electrical system, and meets or exceeds all ANSI/ISA/CEC/NEC requirements for a secondary process seal. With protection from pressurized fluids, gases and vapors to 1500 psi, it protects people and property in even the most volatile conditions.
Applications for the Secondary Process Seal include any facility with high pressure vessels containing explosive or combustible fluids, vapors and gases. These include oil and gas distribution and storage, petroleum refining, petrochemical, pharmaceutical, air separation and handling, and various military facilities.
The Secondary Process Seal with Rupture Sensor by Cooper Crouse-Hinds is the next step in their commitment to ESP (Enhancing Safety & Productivity). The goal behind ESP is to develop smarter, more powerful solutions that enhance safety and productivity. This promise is what drives Cooper Crouse-Hinds to continually develop products that anticipate customer needs and that work to achieve the goal of eventually making danger in the workplace obsolete.
